Centrifugal humidifier



Sept. 6, 1932. w. L. DUDLEY CENTRIFUGAL HUMIDIFIER Filed Sept. 22, 19262 Sheets-Sheet l P 6, 1932- w. L.- DUDLEY 1,875,711

CENTRIFUGAL HUMIDIFIER Filed Sept. 22, 1926 2 Shee ts-Sheet 2 INVENTORM/Mm 2131/0415) 0/ ATTORNEY Patented Sept. 6, 1932 UNITED' STATESPATENT, OFFICE" 3 WILLIAM LYLE DUDLEY, or SEATTLE, wasnmeron cnnrarruen.nunmrrmu' Application flled' September 22, 1928. Serial No. 187,025.

ventilation to properly humidify air, that. is,

add to the air sufiicient moisture to raise its relative humidity, orits absolute humidity to a degree where it is pleasant and healthful tothe occupants of the building ventilated.

15 Dry air, or air lacking in proper moisture content, is deleterious tobody tissues, as it extracts moisture from these tissues, giving rise toirritation of the membranes and a. feeling of bodily discomfort.

Recent investigations have shown that there is a range of relativehumidities for given temperatures that tend to body'comfort.- Mechanicalmeans are and have been ventilation have usually consisted of separateunits of humidifier and an air distributing means, or fan. Theseseparate units of air humidifier and fan are expensive. Each is designedseparately for the purpose intended, are often fabricated by differentmanufacturers and occupy with their connections and auxiliariesconsiderable valuable space in the building. It is the object of myinvention to combine the humidifier and fan into one unit to efi'ectextreme compactness, lower cost of manufacture by allowing thefabrication of the combined humidifier and fan unit by one manfacturer,decreasethe weight by the avoidance of duplicate parts, as for instance,the fan casing acts as a casing for both the fan wheel and humidifier,and

centralize the responsibility for satisfactory and properly distributethe water necessary employed to add moisture to the air to improveventilating conditions. Such means as have heretofore been employed inmechanical for humidification that it may come into intimate andcomplete contact with the air passing through the fan. .Within thevolute casing and exterior to the outer periphery I of the wheel in thepath of the outflowing humidified air are placed zigzag plates, oreliminators, whose purpose is to remove the free moisture or minutedrops of water from v the air before it is distributed for ventilatingpurposes. This free moisture, if not removed, is destructive to interiordecorations,

and deposits on room furniture and fittings which is undesirable. Theseeliminator plates, as herein shown, are preferably laced vertically,although they may be place horizontally or at an angle and within theeasing or an extension thereof. Water, ref erably in the form of a mist,is intro uced at the eye, or inlet, of the fan, or within the casingorboth, depending on the degree of saturation desired, and is carried bythe air entering the wheel through the 'wheel and into the casing in theform of mist or finely divided water particles.

The air, being in intimate contact with the water mist in the interiorof the casing, has its absolute humidity increased providing it is notsaturated at the dry bulb temperature at which it asses through the fan.

There is aheat ,exc ange between the air and the water due to the changeof state fromwater to water vapor as the air tendsto become saturated,and heat is extracted from-the air and the dr bulb temperature of theair is lowered. ere two purposes are realized, the absolute humidity ofthe air is increased and atthe same time its dry bulb temperature islowered. The lowerin of the dry bulb temperature is very desira Is forcooling in the-summer and for various in{ dustrial purposes- Theincrease in humidity is desirable for comfort and for certain industrialpurposes.

A still further object is to provide means for washing the air in suchmanner as to remove a large percentage of dust and dirt.

In accomplishing the various objects of the invention, I have providedthe improved details of construction, the preferred forms :00

of which are illustrated in the accompanying drawings, wherein-- Fi ure1 is a perspective view of a humidi er unit embodied by the presentinvention.

Figure 2 is a horizontal sectional view through the same.

Figure 3 is a side elevation and partial sectional view of the device.

Referring more in detail to the drawings 1 designates the fan casing, ofvolute form, having acircular air inlet 2 at one side, which is locatedconcentrically with respect to the axis of a fan 3 contained within thecasing and operatively supported on one end of a driving shaft 4 whichextends through the wall of the casing opposite the opening 2 and isrevolubly supported in bearings 5 and 6 on a supporting base 7 that maybe secured to the casing. A pulley 8 is fixed on the shaft between thebearings over which a belt may operate to drive the fan.

The fan used is of the multiple blade, turbine type which, in operation,draws in air through opening 2 and then forcibly discharges it throughthe outlet portion 9 of the volute casing. The blades 10 of the fan arefixed to a hub plate 11 that is keyed on the driving shaft 4. They areset at the proper angle to create suction through the opening 2 and topropel air from the casing through the outlet. The inner edges of theseveral blades lieon the surface of a cone which converges inwardly fromthe opening 2 and overlying these edges and secured to the blades is ascreen 12 through which all air entering v the casing through the fanmust pass.

' a pipe 24.

Located centrally of the opening 2 is a spraying device, or nozzle, 15,by means of which a spray of water may be discharged in all directionsagainst the screen. This spray device is connected by means of a pipe 16with a centrifugal pump 17 which is driven by an electric motor 18 toforcibly deliver water to the spray. A supply of water for this purposeis maintained in a sump or basin 19 that is provided as a part of thecasing and which is connected by means of a pipe 20 with the pump. Anoutwardlydirected, conical flange 21 is provided about the opening 2 andthis has an inwardly directed conical flange 22 fixed thereto andextending within the outer periphery of the screen, as shown in Figure2, to catch or collect water that is cast outwardly from the fan, andwater so collected is delivered to the lower part of the casing andflows back to the sump through Located within the outlet 9 of the casingis .a plurality of vertically fixed, and spaced apart eliminator plates25 against which the air impinges as it is driven from the fan.

and these prevent direct passage of air and function as baflies tocollect and remove free moisture or drops of water from the air.

about its outer side.

The water that is thus collected flows into a transverse trough 30across the base of the outlet and is delivered by a pipe 31 into thesump 19.

The fan casing in its volute form provides an airway, or passage ofincreasing proportions from the inlet to the outlet of the easing andthe intaken air passing through the water distributing means in theinlet is thereby caused to expand during its travel to the outlet andwhile in intimate contact with the water particles carried from thedistributing means. This increase in proportions, or dimensions, of theairway incidentally slows up the speed of the air current therebyincreasing the time of contact of air and atom ized water to thus giveadded efficiency to the system.

In use, the pump operates to deliver water, in the form of a fine spray,onto the screen mesh 12 supported by the revolving fan; This waterspreads out in a thin film allowing intimate contact with the air inpassing through the mesh and fan wheel blades, increasing the ability ofthe air to absorb moisture in its passage through the wheel.

In this arrangement the air also absorbs moisture by passing through thespray or cated. in dotted lines in Figure 2,and which connects with thewater pipe 16.

It is readily apparent that changes in de- I tails of construction, suchas position of the sump, the pump and motor and water connections, couldbe made without departing from the spirit of the invention, and alsothat the means of operating the fan could be altered to meet specialconditions, and for this reason, I do not wish to be limited only to thedevice as herein illustrated.

It is further to be understood that the fan need not be confined to theexact form shown. It may be conical, cylindrical or fiat and the screenmay be located within it, as shown, or Also; the eliminator 25 may alsobe located in the fan housing or at some distance from the fan.

Having thus described my invention, what I claim as new therein anddesire to secure by Letters Patent, is:

1. In combination, a volute fan casing having an air inlet at one sideand an outlet at the end, a fan wheel, having blades in circulararrangement, mounted within the casing and alined with said air inletand revoluble to draw air into the casing through the inlet and toforcibly discharge it through said outlet, a screen fitted to the inneredges of said fan blades and through which all air must pass in enteringthe casing, a spray device mounted adjacent the air inlet to deliverwater in a fine spray or film against the fan and through which all airentering the casing must pass, and eliminator plates mounted in "the.outlet for collecting free moisture from the air in passing.

2. In combination, a volute fan casing having an air inlet opening atone side and'a discharge opening at the end, a fan driving shaftextended int-o the casing concentric of the air inlet, a fan Wheel fixedon the shaft having its blades arranged circularly with their inneredges lying in the surface of a cone, a screen fixed to the inner edgesof the blades and through Which the air must pass in entering thecasing, a spray device mounted adjacent the air inlet for deliveringwater in a fine spray against the screen, eliminator plates mounted inthe outlet for collecting free moisture from the air in passing, a sumpfor containing a Water supply, means for conducting Water, dischargedfrom the fan and collected by said eliminators, into the sump, and apump operable to supply the spray device with Water from the sump.

Signed at Seattle, Washington this 16th day of July, 1926.

WILLIAM LYLE DUDLEY.

